Why Do Cars Make Noise When Shifting into Reverse? High-Pitched Noise Is a Direct Result of the Type of Gear Used Exclusively for This Function of the Transmission

Written by Felipe Alves da Silva

Published on 18/06/2025 at 11:21

Marcha à ré tem um som único que começa no movimento da alavanca.

Be the first to react!

Sharp Noise When Reversing Is Caused By The Straight-Toothed Gear Design, Unlike That Used In Normal Gears, Which Are Quieter And Smoother

When engaging the reverse gear and accelerating the vehicle, a sharp and characteristic noise can be heard. This noise, common in various cars, does not indicate a mechanical defect, but is explained by the type of gear used in the cars’ reversal system.

The majority of forward gears use gears with helical teeth, which ensure progressive and smooth contact between components, significantly reducing noise and wear over time. In contrast, the reverse gear adopts straight-toothed gears, whose contact occurs simultaneously and directly.

This difference in the shape of the mechanical parts is the main reason for the noise. The abrupt contact between the straight teeth generates more vibration and, consequently, more noise, as well as greater wear over continuous use.

ARTICLE CONTINUES BELOW

See also

Automotive mechanics specialist Daniel Monteiro explains that the sound of the reverse gear is a natural consequence of this design. He emphasizes that, despite the auditory discomfort, it is a completely expected effect and poses no risk to the vehicle.

According to a report published by CNN Brasil, the use of this type of gear is common because it is cheaper and more efficient in quick maneuvers, where sound comfort is not a priority.

Why Do Cars Make Noise When Shifting into Reverse? High-Pitched Noise Is a Direct Result of the Type of Gear Used Exclusively for This Function of the Transmission

Sharp Noise When Reversing Is Caused By The Straight-Toothed Gear Design, Unlike That Used In Normal Gears, Which Are Quieter And Smoother

While an average building in London or New York takes three years to be completed, in China a 26-story tower went up in five days with about 100 workers, and the global modular construction market already moves US$ 95 billion per year.

A Chinese factory in Guangdong is assembling a humanoid robot every 30 minutes while Tesla, Figure, and Boston Dynamics still struggle to deliver 10 thousand per year.

Australia installs giant concrete structures on the seabed 800 meters from the shore to create an ocean intake for desalination that will draw in saltwater and produce 30 million liters of drinking water per day.

Secret chamber sealed 4,500 years ago found in the Pyramid of Khufu, and Hawass announces its opening to the world in 2026

A public school student single-handedly created a machine capable of treating water for up to 50 people using only solar energy. It was awarded third place at one of the most important science fairs in the world.

While cities spend fortunes patching potholes and tons of plastic become waste, the Netherlands transforms over 218,000 recycled cups into a modular bike path that can conceal drainage, cables, and pipes.

While communities suffer from water scarcity and the advancing desert, women in Morocco use nets high up in the mountains to trap fog droplets, fill reservoirs, and transport drinking water through more than 10 km of piping.

A perfect 6 km ring in the far east of Russia intrigues NASA satellites as it appears to be a meteor crater or an extinct volcano, but the agency has already confirmed that it is neither and harbors a much stranger origin beneath the Earth.

Australia positions a barge with 78-meter legs at sea to install ocean sockets connected to tunnels under the seabed to supply a desalination plant that will produce 150 million liters of water per day in Alkimos until 2028.

From a simple approach at the gate to more than R$ 45,000 in donations, the story of a gardener offering volunteer work shows how a well-tended garden can pave the way for food, hope, and an almost finished home for a Brazilian family.

Couple buys 380 seedlings online to create an 80-meter hedge on their property, tests drip irrigation, and begins transforming open area into a green wall at the refuge they are building in Santa Catarina.

3.09-carat white diamond found by woman in a United States park after losing her father and son, and the rare stone valued at up to R$ 240,000 becomes a symbol of unexpected joy during a period of mourning

Why Do Cars Make Noise When Shifting into Reverse? High-Pitched Noise Is a Direct Result of the Type of Gear Used Exclusively for This Function of the Transmission

Sharp Noise When Reversing Is Caused By The Straight-Toothed Gear Design, Unlike That Used In Normal Gears, Which Are Quieter And Smoother

While an average building in London or New York takes three years to be completed, in China a 26-story tower went up in five days with about 100 workers, and the global modular construction market already moves US$ 95 billion per year.

A Chinese factory in Guangdong is assembling a humanoid robot every 30 minutes while Tesla, Figure, and Boston Dynamics still struggle to deliver 10 thousand per year.

Australia installs giant concrete structures on the seabed 800 meters from the shore to create an ocean intake for desalination that will draw in saltwater and produce 30 million liters of drinking water per day.

Secret chamber sealed 4,500 years ago found in the Pyramid of Khufu, and Hawass announces its opening to the world in 2026

A public school student single-handedly created a machine capable of treating water for up to 50 people using only solar energy. It was awarded third place at one of the most important science fairs in the world.

While cities spend fortunes patching potholes and tons of plastic become waste, the Netherlands transforms over 218,000 recycled cups into a modular bike path that can conceal drainage, cables, and pipes.

While communities suffer from water scarcity and the advancing desert, women in Morocco use nets high up in the mountains to trap fog droplets, fill reservoirs, and transport drinking water through more than 10 km of piping.

With an updated oil-bathed belt, the 2026 Chevrolet Onix and Onix Plus arrive with discounts of up to R$ 23,000, fuel consumption of up to 19.7 km/l, a range of 866 km, a 115 hp turbo engine, and a 5-year warranty.

Man transforms automotive engine into a functional nautical system, adapts cooling with external water, installs shaft, propeller, and anti-corrosion protection, and creates a low-cost handcrafted yacht capable of safely navigating using repurposed parts and a structure reinforced with fiberglass.

While electric cars die in four hours, the British Hydromax aims to be the fastest hydrogen car in the world with 1,600 hp and a target of 563 km/h.

Chinese SUV with three engines, 1,380 hp, and acceleration from 0 to 100 km/h in 2.96 seconds debuts with ultra-fast charging and promises up to 1,416 km of total range for long trips in high modern luxury.

Are diesel trucks numbered? Volvo says the new electric generation can already replace traditional models.

A perfect 6 km ring in the far east of Russia intrigues NASA satellites as it appears to be a meteor crater or an extinct volcano, but the agency has already confirmed that it is neither and harbors a much stranger origin beneath the Earth.

Australia positions a barge with 78-meter legs at sea to install ocean sockets connected to tunnels under the seabed to supply a desalination plant that will produce 150 million liters of water per day in Alkimos until 2028.

From a simple approach at the gate to more than R$ 45,000 in donations, the story of a gardener offering volunteer work shows how a well-tended garden can pave the way for food, hope, and an almost finished home for a Brazilian family.

Couple buys 380 seedlings online to create an 80-meter hedge on their property, tests drip irrigation, and begins transforming open area into a green wall at the refuge they are building in Santa Catarina.

3.09-carat white diamond found by woman in a United States park after losing her father and son, and the rare stone valued at up to R$ 240,000 becomes a symbol of unexpected joy during a period of mourning